I've only seen NutnFancy's review of the X95. Based on that, I find absolutely no reason to pursue the X95, as it seems to offer few, if any, advantages over the Tavor due to import restrictions.
As far as the Tavor vs the RDB, the verdict remains unclear. The RDB has been stopped (to the point of needing complete takedown) by mud infiltration, whereas the Tavor will put gas in your face if you use a suppressor. The cost difference is already obvious; the RDB is a bargain if you can find it. Both rifles are ergonomically sound, with only minor issues related to their both being so short. The integrated sights on the Tavor are kinda nice, folding into the rail so that they don't get in the way, but if you plan on mounting a magnified optic then this is academic. The RDB is a little lighter. The trigger is probably the biggest thing. The Tavor has a modular trigger that sucks, but can be replaced, whereas all reports on the RDB say that the trigger is the best of any of the bullpups ever made.
The RDB is cleverly designed, versatile, light, and apparently as tough as most things, as long as you don't toss it into a mud pit.